DOCSLIB.ORG

Nihal İKİZOĞLU Kimyaakademi.Com 1 MOSELEY and MODERN

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Nihal İKİZOĞLU Kimyaakademi.Com 1 MOSELEY and MODERN Nihal İKİZOĞLU MOSELEY and MODERN PERIODIC TABLE (designed by atomic numbers of elements) kimyaakademi.com 1 Nihal İKİZOĞLU PERIODS: Period number = Number of basic energy levels = The principal quantum number • The horizontal lines in the periodic system are called periods. • There are 7 periods. • The physical and chemical properties of these elements are different if they contain different numbers of electrons at the outermost energy level of the same periodic elements. The 14 elements of the 6th period is placed under the table. These are called lanthanides. In Period 7, 14 elements are placed under the table. These are called actinides. GROUPS: • Vertical columns in the periodic table are called groups. • There are two types of groups, A and B. There are 8 A and 10 B groups. • A groups are also called main groups. • Group B transition elements (beginning at the 4th period) • Elements in the same group show similar physical and chemical properties. PLACES of ELEMENTS in the PERIODIC TABLE The number of electrons at the outermost energy level of elements are called valence electrons and they determine the group number in the periodic table. Ø If the electronic configuration of an element ends with s or p orbital, it means this element is in one of the A groups. d or f orbital, it means this element is in one of the B groups. Question: a) Write the electron sequence of the elements given in the table below and specify in which period and group these elements are included. Element Electron Configuration Period Group 11Na 8O 20Ca 2He 17Cl 18Ar b) Which elements have similar chemical properties? kimyaakademi.com 2 Nihal İKİZOĞLU Question: What is the atomic number of the element in group 5A of period 3 of the periodic system? Question: What is the atomic number of the element in 4th period and group 2B of periodic system? +3 Question: Find the period and the group of 21Sc ion. -2 Question: Find the period and the group of 16S ion. +3 + Question: 13X and Y ions have the same number of electron. So, find the place of Y element in the periodic table. Question: Find the places of the following elements in the periodic system. 12Mg: 7N: 13Al: 20Ca: 17Cl: 24Cr: 25Mn: 35Br: 53I: 87Fr: kimyaakademi.com 3 Nihal İKİZOĞLU Question: H He Li C N O Ne Na Mg Si Cl Ca Sc Cr Fe Co Ga Ge Answer the following questions about the elements shown in the periodic table. a) Which elements are placed in the 4th period? ............................................................................................................ b) Which elements are placed in group 2A? ............................................................................................................ c) Which elements are placed in group B? ............................................................................................................ d) Which elements are on the s-block? ............................................................................................................ e) Which element has the greatest atomic number? ............................................................................................................ f) Which element has the smallest atom number? ............................................................................................................ g) Which elements are alkaline metals? ............................................................................................................ h) Which element has valence orbitals as ns2 np6? ............................................................................................................ i) Which elements have full-filled valence orbitals? ............................................................................................................ j) What is the element with similar chemical properties with Mg? ............................................................................................................ kimyaakademi.com 4 Nihal İKİZOĞLU PERIODIC CHANGES OF ELEMENTS ATOMIC RADIUS: The distance between the atomic nucleus and the electron at the farthest distance from the nucleus. 1) Covalent Radius: A radius calculated from the distance between two atoms of a covalently bonded nucleus. 75 pm 2) Ionic Radius: It is measured from the distance between the nuclei of bonded ions. 3) Van der Waals Radius: Where two atoms or molecules of the same genus are closest to each other without a bond, half of the distance between the nuclei is called Van der Waals radius. r = 184 pm N2 N2 G Radius between noble gases is also known as Van der Waals radius. Question: a c Fe-Fe He-He b d F-F CO Name the radiuses of the atoms or groups of atoms given above. kimyaakademi.com 5 Nihal İKİZOĞLU - Question: Na Na+ Cl + Cl2 à Which of the followings are correct according to the above reaction? I. The radius of the atom that loses electrons decreases. II. The radius of the atom that gains electrons increases. III. Attractive forces of Na nucleus increases. Radii of Isoelectronic Particles: « As the proton numbers increase on the isoelectronic particles, the radius decreases. Question: Rank the radius of the ions below. -3 +1 -4 +3 -1 +2 -2 7N , 11Na , 6C , 13Al , 9F , 12Mg , 8O ………………………………………………………………………… Change of Atomic Radius in Periodic Table In the same group: "The radius of the atom increases decrease as we go down from top to bottom." The number of energy levels down in each group increases, which means that the electron cloud around the nucleus is expanding. In the same period: "The radius of the atom usually decreases from left to right." As we go to the right, the number of protons increases by the number of electrons. increase Increasing the number of protons increases the attraction of the nucleus. So the radius gets smaller. Snowman facing to the right Question: Arrange the radii of the atoms given below from small to large. 19K, 20Ca, 35Br è …………………………………… Question: Check the following statements; put T in case of true and F in case of wrong. a) The atomic radii of all the elements in a group are equal to each other. ......... b) The radius of atoms bound by ionic bonds is called the ionic radius. ......... c) For ions known to be isoelectronic, the radius of the ion with the larger ionic charge is smaller. ......... d) The relationship between the radii of the phosphorus particles is P-3> P > P+5. ......... kimyaakademi.com 6 Nihal İKİZOĞLU Question: Arrange the radii of the atoms given below from small to large. a) 11Na and 17Cl ……………………………… b) 4Be and 12Mg ……………………………… Question: Determine how the following quantities change when atoms 20Ca and 8O reach to octet by giving/gaining electrons. 20Ca 8O a) Number of electrons b) Atomic number c) Atomic diameter d) Attractive force per each electron e) Electrical charge of the nucleus Question: Compare the diameters of the following elements. -3 -2 + a) 7N , 8O , 10Ne, 11Na -2 +4 +6 b) 16X, 16X , 16X , 16X IONIZATION ENERGY Ionization energy of an element is the energy needed to remove the outermost, or highest energy, electron from a neutral atom in the gas phase. + - st X(g) + E1 à X (g) + e (E1 = 1 I. E.) + +2 - nd X (g) + E2 à X (g) + e (E2 = 2 I. E.) +2 +3 - rd X (g) + E3 à X (g) + e (E3 = 3 I. E.) +3 - X(g) + Ex à X (g) + 3e (Ex = ………………………) kimyaakademi.com 7 Nihal İKİZOĞLU Change of Ionization Energy in Periodic Table « In the same period ionization energy generally increases as the radius of the atom decreases from the left to the right. « In the same group, the ionization energy decreases as the atomic radius increases as we move downward. « During the period there are some irregularities that break the general rule. For example; G Removing an electron from the p orbital of the increase Al atom, which is half full, is much easier than removing the electron from the fully charged s orbital of the Mg atom. Therefore, the first ionization energy of the 3A group elements is I.E. smaller than the first ionization energy of the 2A increase Increases to up group elements. and right G The same situation occurs between group 5A and group 6A. The ionization energy of group 6A is less than 5A. ð Ionization energy change in the same period: 1A < 3A < 2A < 4A < 6A < 5A < 7A < 8A st Question: Compare the 1 ionization energies of the 15P and 16S elements. Explain why? kimyaakademi.com 8 Nihal İKİZOĞLU Determination of group number by examining the ionization energy values of elements The ionization energy value of each element always increases. However, this increase is too much in one place. The observation of an increase of at least 4 times or more between two consecutive ionization energies indicates that a noble gas electron system is encountered. This increase; - - If between IE1 and IE2, the element is in group 1A (Valence e number = 1) - - If between IE2 and IE3, the element is in group 2A (Valence e number = 2) - - If between IE3 and IE4, the element is in group 3A (Valence e number = 3) - So on… Question: Find the group numbers of X, Y and Z main group elements whose ionization energy values are given. ELEMENT 1st I.E. 2nd I.E. 3rd I.E. 4th I.E. X 215 420 3548 5019 Y 191 580 875 5978 Z 176 348 1847 2519 ELECTRON AFFINITY Electron affinity is the change in energy of a neutral atom (in the gaseous phase) when an electron is added to the atom to form a negative ion. - - X(g) + e à X (g) + Q increase ¯ Metals and noble gases do not tend to gain electrons. Electron affinity increase ¯ Elements of group 7A have the highest electron increases to up affinity. and rigth kimyaakademi.com 9 Nihal İKİZOĞLU ELECTRONEGATIVITY • Electronegativity is a measure of the tendency of an increase atom to attract a bonding pair of electrons. • Fluorine (the most electronegative element) is assigned a value of 4.0, and values range down to cesium and francium which are the least Electronegativity increase electronegative at 0.7. increases to up • Noble gases have no electronegativity values. and rigth • The Pauling scale is the most commonly used. If the electronegativity difference between the elements is very small, the bonding electrons are used together and the bond is covalent. If the difference is too large, the bond electrons are on the side of electronegativity excess and the bond is ionic.
Load more

Recommended publications
  • ATOMIC RADII of the ELEMENTS References
    ATOMIC RADII OF THE ElEMENTS The simple model of an atom as a hard sphere that can approach The Cambridge Crystallographic Data Center also makes use only to a fixed distance from another atom to which it is not bond- of a set of “covalent radii” to determine which atoms in a crystal ed has proved useful in interpreting crystal structures and other are bonded to each other . Thus two atoms A and B are judged to molecular properties . The term van der Waals radius, rvdw, was be connected by a covalent bond if their separation falls within a originally introduced by Pauling as a measure of this atomic size . tolerance of ±0 .4 Å of the sum rcov (A) + rcov (B) . The covalent radii Thus in a closely packed structure two non-bonded atoms A and are given in the fourth column of the table . B will be separated by the sum of their van der Waals radii rvdw (A) and rvdw (B) . The set of van der Waals radii proposed by Pauling References was refined by Bondi (Reference 1) based on crystallographic data, gas kinetic collision cross sections, and liquid state properties . The 1 . Bondi, A ., J. Phys. Chem. 68, 441, 1964 . non-bonded contact distances predicted from the recommended 2 . Rowland, R . S . and Taylor, R ., J. Phys. Chem. 100, 7384, 1996 . 3 . Cambridge Crystallographic Data Center, www .ccdc .cam .ac .uk/prod- r of Bondi have been compared with actual data in the collec- vdw ucts/csd/radii/ tion of the Cambridge Crystallographic Data Center by Rowland and Taylor (Reference 2) and modified slightly .
    [Show full text]
  • Atomic and Ionic Radii of Elements 1–96 Martinrahm,*[A] Roald Hoffmann,*[A] and N
    DOI:10.1002/chem.201602949 Full Paper & Elemental Radii Atomic and Ionic Radii of Elements 1–96 MartinRahm,*[a] Roald Hoffmann,*[a] and N. W. Ashcroft[b] Abstract: Atomic and cationic radii have been calculated for tive measureofthe sizes of non-interacting atoms, common- the first 96 elements, together with selected anionicradii. ly invoked in the rationalization of chemicalbonding, struc- The metric adopted is the average distance from the nucleus ture, and different properties. Remarkably,the atomic radii where the electron density falls to 0.001 electrons per bohr3, as defined in this way correlate well with van der Waals radii following earlier work by Boyd. Our radii are derived using derived from crystal structures. Arationalizationfor trends relativistic all-electron density functional theory calculations, and exceptionsinthose correlations is provided. close to the basis set limit. They offer asystematic quantita- Introduction cule,[2] but we prefer to follow through with aconsistent pic- ture, one of gauging the density in the atomic groundstate. What is the size of an atom or an ion?This question has been The attractivenessofdefining radii from the electron density anatural one to ask over the centurythat we have had good is that a) the electron density is, at least in principle, an experi- experimental metricinformation on atoms in every form of mental observable,and b) it is the electron density at the out- matter,and (more recently) reliable theory for thesesame ermost regionsofasystem that determines Pauli/exchange/ atoms. And the momentone asks this question one knows same-spinrepulsions, or attractive bondinginteractions, with that there is no unique answer.Anatom or ion coursing down achemical surrounding.
    [Show full text]
  • ARC: an Open-Source Library for Calculating Properties of Alkali Rydberg Atoms
    ARC: An open-source library for calculating properties of alkali Rydberg atoms N. Šibalic´a,∗, J. D. Pritchardb, C. S. Adamsa, K. J. Weatherilla aJoint Quantum Center (JQC) Durham-Newcastle, Department of Physics, Durham University, South Road, Durham, DH1 3LE, United Kingdom bDepartment of Physics, SUPA, University of Strathclyde, 107 Rottenrow East, Glasgow, G4 0NG, United Kingdom Abstract We present an object-oriented Python library for computation of properties of highly-excited Rydberg states of alkali atoms. These include single-body effects such as dipole matrix elements, excited-state lifetimes (radiative and black-body limited) and Stark maps of atoms in external electric fields, as well as two-atom interaction potentials accounting for dipole and quadrupole coupling effects valid at both long and short range for arbitrary placement of the atomic dipoles. The package is cross-referenced to precise measurements of atomic energy levels and features extensive documentation to facilitate rapid upgrade or expansion by users. This library has direct application in the field of quantum information and quantum optics which exploit the strong Rydberg dipolar interactions for two-qubit gates, robust atom-light interfaces and simulating quantum many-body physics, as well as the field of metrology using Rydberg atoms as precise microwave electrometers. Keywords: Alkali atom, Matrix elements, Dipole-dipole interactions, Stark shift, Förster resonances PROGRAM SUMMARY They are a flourishing field for quantum information process- Program Title: ARC: Alkali Rydberg Calculator ing [1, 2] and quantum optics [3, 4, 5] in the few to single exci- Licensing provisions: BSD-3-Clause tation regime, as well as many-body physics [6, 7, 8, 9, 10, 11], Programming language: Python 2.7 or 3.5, with C extension in the many-excitations limit.
    [Show full text]
  • Chalcogen-Nitrogen Bond: Insights Into a Key Chemical Motif
    Proceedings Chalcogen-nitrogen Bond: Insights into A Key Chemical Motif Marco Bortoli,1 Andrea Madabeni,1 Pablo Andrei Nogara,2 Folorunsho B. Omage,2 Giovanni Ribaudo,3 Davide Zeppilli,1 Joao Batista Teixeira Rocha,2* Laura Orian1* 1 Dipartimento di Scienze Chimiche Università degli Studi di Padova Via Marzolo 1 35131 Padova, Italy; [email protected] (M.B.); [email protected] (A.M..); [email protected] (D.Z.) 2 Departamento de Bioquímica e Biologia Molecular, Universidade Federal de Santa Maria, Santa Maria, 97105-900, RS Brazil; [email protected] (P.A.N.); [email protected] (F.B.O.) 3 Dipartimento di Medicina Molecolare e Traslazionale, Università degli Studi di Brescia, Viale Europa 11, 25123 Brescia, Italy; [email protected] (G.R.) * Correspondence: : [email protected] (J.B.T.R), [email protected] (L.O.); † Presented at the 1st International Electronic Conference on Catalysis Sciences, 10–30 November 2020; Available online: https://eccs2020.sciforum.net/ Published: 10 November 2020 Abstract: Chalcogen-nitrogen chemistry deals with systems in which sulfur, selenium or tellurium is linked to a nitrogen nucleus. This chemical motif is a key component of different functional structures, ranging from inorganic materials and polymers to rationally designed catalysts, to bioinspired molecules and enzymes. The formation of a selenium-nitrogen bond, and its disruption, are rather common events in organic Se-catalyzed processes. In nature, along the mechanistic path of glutathione peroxidase, evidence of the formation of a Se-N bond in highly oxidizing conditions has been reported and interpreted as a strategy to protect the selenoenzyme from overoxidation.
    [Show full text]
  • Van Der Waals Radii of Elements S
    Inorganic Materials, Vol. 37, No. 9, 2001, pp. 871–885. Translated from Neorganicheskie Materialy, Vol. 37, No. 9, 2001, pp. 1031–1046. Original Russian Text Copyright © 2001 by Batsanov. Van der Waals Radii of Elements S. S. Batsanov Center for High Dynamic Pressures, Mendeleevo, Solnechnogorskii raion, Moscow oblast, 141570 Russia Received February 14, 2001 Abstract—The available data on the van der Waals radii of atoms in molecules and crystals are summarized. The nature of the continuous variation in interatomic distances from van der Waals to covalent values and the mechanisms of transformations between these types of chemical bonding are discussed. INTRODUCTION der Waals radius with the quantum-mechanical require- ment that the electron density vary continuously at the The notion that an interatomic distance can be periphery of atoms. thought of as the sum of atomic radii was among the most important generalizations in structural chemistry, In this review, the van der Waals radii of atoms eval- treating crystals and molecules as systems of interact- uated from XRD data, molar volumes, physical proper- ing atoms (Bragg, 1920). The next step forward in this ties, and crystal-chemical considerations are used to area was taken by Mack [1] and Magat [2], who intro- develop a universal system of van der Waals radii. duced the concept of nonvalent radius (R) for an atom situated at the periphery of a molecule and called it the atomic domain radius [1] or Wirkungsradius [2], ISOTROPIC CRYSTALLOGRAPHIC implying that this radius determines intermolecular dis- VAN DER WAALS RADII tances. Later, Pauling [3] proposed to call it the van der Kitaigorodskii [4, 5] was the first to formulate the Waals radius, because it characterizes van der Waals principle of close packing of molecules in crystalline interactions between atoms.
    [Show full text]
  • Quantum-Mechanical Relation Between Atomic Dipole Polarizability and the Van Der Waals Radius (Supplemental Material)
    Quantum-Mechanical Relation between Atomic Dipole Polarizability and the van der Waals Radius Dmitry V. Fedorov,1, ∗ Mainak Sadhukhan,1 Martin St¨ohr,1 and Alexandre Tkatchenko1 1Physics and Materials Science Research Unit, University of Luxembourg, L-1511 Luxembourg The atomic dipole polarizability, α, and the van der Waals (vdW) radius, RvdW, are two key quantities to describe vdW interactions between atoms in molecules and materials. Until now, they have been determined independently and separately from each other. Here, we derive the quantum- 1/7 mechanical relation RvdW = const. × α which is markedly different from the common assumption 1/3 RvdW ∝ α based on a classical picture of hard-sphere atoms. As shown for 72 chemical elements between hydrogen and uranium, the obtained formula can be used as a unified definition of the vdW radius solely in terms of the atomic polarizability. For vdW-bonded heteronuclear dimers consisting of atoms A and B, the combination rule α = (αA + αB )/2 provides a remarkably accurate way to calculate their equilibrium interatomic distance. The revealed scaling law allows to reduce the empiricism and improve the accuracy of interatomic vdW potentials, at the same time suggesting the existence of a non-trivial relation between length and volume in quantum systems. The idea to use a specific radius, describing a distance by Bondi [8] has been extensively used. However, it is an atom maintains from other atoms in non-covalent in- based on a restricted amount of experimental informa- teractions, was introduced by Mack [1] and Magat [2]. tion available at that time. With the improvement of Subsequently, it was employed by Kitaigorodskii in his experimental techniques and increase of available data, theory of close packing of molecules in crystals [3, 4].
    [Show full text]
  • Recent Developments in Chalcogen Chemistry
    RECENT DEVELOPMENTS IN CHALCOGEN CHEMISTRY Tristram Chivers Department of Chemistry, University of Calgary, Calgary, Alberta, Canada WHERE IS CALGARY? Lecture 1: Background / Introduction Outline • Chalcogens (O, S, Se, Te, Po) • Elemental Forms: Allotropes • Uses • Trends in Atomic Properties • Spin-active Nuclei; NMR Spectra • Halides as Reagents • Cation Formation and Stabilisation • Anions: Structures • Solutions of Chalcogens in Ionic Liquids • Oxides and Imides: Multiple Bonding 3 Elemental Forms: Sulfur Allotropes Sulfur S6 S7 S8 S10 S12 S20 4 Elemental Forms: Selenium and Tellurium Allotropes Selenium • Grey form - thermodynamically stable: helical structure cf. plastic sulfur. R. Keller, et al., Phys. Rev. B. 1977, 4404. • Red form - cyclic Cyclo-Se8 (cyclo-Se7 and -Se6 also known). Tellurium • Silvery-white, metallic lustre; helical structure, cf. grey Se. • Cyclic allotropes only known entrapped in solid-state structures e.g. Ru(Ten)Cl3 (n = 6, 8, 9) M. Ruck, Chem. Eur. J. 2011, 17, 6382 5 Uses – Sulfur Sulfur : Occurs naturally in underground deposits. • Recovered by Frasch process (superheated water). • H2S in sour gas (> 70%): Recovered by Klaus process: Klaus Process: 2 H S + SO 3/8 S + 2 H O 2 2 8 2 • Primary industrial use (70 %): H2SO4 in phosphate fertilizers 6 Uses – Selenium and Tellurium Selenium and Tellurium : Recovered during the refining of copper sulfide ores Selenium: • Photoreceptive properties – used in photocopiers (As2Se3) • Imparts red color in glasses Tellurium: • As an alloy with Cu, Fe, Pb and to harden
    [Show full text]
  • Monte Carlo Simulations of Polonium Drift from Radon Progeny in an Electrostatic Counter
    Monte Carlo Simulations of Polonium Drift from Radon Progeny in an Electrostatic Counter Devon Seymour Advised by Richard Gaitskell Brown University, Dept. of Physics, Providence RI 02912, USA May 4, 2017 1 Physics Motivation During the past two decades, a standard cosmological picture of the universe (the Lambda Cold Dark Matter or LCDM model) has emerged, which includes a detailed breakdown of the main constituents of the energy density of the universe. This theoretical framework is now on a firm empirical footing, given the remarkable agreement of a diverse set of astrophysical data. Recent results by Planck largely confirm the earlier Wilkinson Microwave Anisotropy Probe (WMAP) conclusions and confirm that the universe is spatially flat, with an acceleration in the rate of expansion and an energy budget comprising approximately 5% baryonic matter, 26% cold dark matter (CDM), and 69% dark energy[1]. Astrophysical measurements on mul- tiple length scales show that dark matter is consistent with like a particle model and not a modification of gravity. Grav- itational lensing of distant galaxies by foreground galactic clusters can provide a map of the total gravitational mass, showing that this mass far exceeds that Figure 1: LZ sensitivity projections. The of ordinary baryonic matter. baseline LZ assumptions give the solid black curve. LUX and ZEPLIN results The LUX-ZEPLIN (LZ) experiment are shown in broken blue lines. If LZ achieves its design goals (e.g., reducing the will attempt to establish the existence of radon background), the sensitivity would a type of dark matter known as WIMPs improve, resulting in the magenta sensi- tivity curve.
    [Show full text]
  • Python Module Index 79
    mendeleev Documentation Release 0.9.0 Lukasz Mentel Sep 04, 2021 CONTENTS 1 Getting started 3 1.1 Overview.................................................3 1.2 Contributing...............................................3 1.3 Citing...................................................3 1.4 Related projects.............................................4 1.5 Funding..................................................4 2 Installation 5 3 Tutorials 7 3.1 Quick start................................................7 3.2 Bulk data access............................................. 14 3.3 Electronic configuration......................................... 21 3.4 Ions.................................................... 23 3.5 Visualizing custom periodic tables.................................... 25 3.6 Advanced visulization tutorial...................................... 27 3.7 Jupyter notebooks............................................ 30 4 Data 31 4.1 Elements................................................. 31 4.2 Isotopes.................................................. 35 5 Electronegativities 37 5.1 Allen................................................... 37 5.2 Allred and Rochow............................................ 38 5.3 Cottrell and Sutton............................................ 38 5.4 Ghosh................................................... 38 5.5 Gordy................................................... 39 5.6 Li and Xue................................................ 39 5.7 Martynov and Batsanov........................................
    [Show full text]
  • Thorium Periodic Table of Elements
    Periodic Table of Elements https://periodic-table.pro/Element/Th/enView online at https://periodic-table.pro Thorium This foil is what remains after useful shapes were stamped out, but what those shapes were useful for remains a mystery. Pure thorium metal like this is quite rare, and not easily obtained. 01. OVERVIEW Symbol Th Atomic number 90 Atomic weight 232.0381 Density 11.724 g/cm³ Melting point 1750 °C Boiling point 4820 °C 02. THERMAL PROPERTIES Phase Solid Melting point 1750 °C Boiling point 4820 °C Absolute melting point 2023 K Absolute boiling point 5093 K Critical pressure N/A Critical temperature N/A Heat of fusion 16 kJ/mol Heat of vaporization 530 kJ/mol Heat of combustion N/A Specific heat 118 J/(kg K) Adiabatic index N/A Neel point N/A Thermal conductivity 54 W/(m K) Thermal expansion 0.000011 K¹ 03. PHYSICAL PROPERTIES Density 11.724 g/cm³ Density (liquid) N/A Molar volume 0.0000197917 Molar mass 232.03806 u Brinell hardness 400 MPa Mohs hardness 3 MPa Vickers hardness 350 MPa Bulk modulus 54 GPa Shear modulus 31 GPa Young modulus 79 GPa Poisson ratio 0.27 Refractive index N/A Speed of sound 2490 m/s Thermal conductivity 54 W/(m K) Thermal expansion 0.000011 K¹ 04. REACTIVITY Valence 4 Electronegativity 1.3 Electron affinity N/A Ionization energies 587, 1110, 1930, 2780 kJ/mol 05. SAFETY Autoignition point 130 °C Flashpoint N/A Heat of combustion N/A 06. CLASSIFICATIONS Alternate names N/A Names of allotropes N/A Block, Group, Period f, N/A, 7 Electron configuration [Rn]6d²7s² Color Silver Discovery 1829 in Sweden Gas phase N/A 07.
    [Show full text]
  • Does Oxygen Feature Chalcogen Bonding?
    molecules Article Does Oxygen Feature Chalcogen Bonding? Pradeep R. Varadwaj 1,2 1 Department of Chemical System Engineering, School of Engineering, The University of Tokyo 7-3-1, Tokyo 113-8656, Japan; [email protected] or [email protected] 2 The National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8560, Japan Received: 20 July 2019; Accepted: 28 August 2019; Published: 30 August 2019 Abstract: Using the second-order Møller–Plesset perturbation theory (MP2), together with Dunning’s all-electron correlation consistent basis set aug-cc-pVTZ, we show that the covalently bound oxygen atom present in a series of 21 prototypical monomer molecules examined does conceive a positive (or a negative) σ-hole. A σ-hole, in general, is an electron density-deficient region on a bound atom M along the outer extension of the R–M covalent bond, where R is the reminder part of the molecule, and M is the main group atom covalently bonded to R. We have also examined some exemplar 1:1 binary complexes that are formed between five randomly chosen monomers of the above series and the nitrogen- and oxygen-containing Lewis bases in N2, PN, NH3, and OH2. We show that the O-centered positive σ-hole in the selected monomers has the ability to form the chalcogen bonding interaction, and this is when the σ-hole on O is placed in the close proximity of the negative site in the partner molecule. Although the interaction energy and the various other 12 characteristics revealed from this study indicate the presence of any weakly bound interaction between the monomers in the six complexes, our result is strongly inconsistent with the general view that oxygen does not form a chalcogen-bonded interaction.
    [Show full text]
  • Theoretical Study of Xenon Adsorption in Uo2nanoporous Matrices Mehdi Colbert, Guy Treglia, Fabienne Ribeiro
    Theoretical study of xenon adsorption in UO2nanoporous matrices Mehdi Colbert, Guy Treglia, Fabienne Ribeiro To cite this version: Mehdi Colbert, Guy Treglia, Fabienne Ribeiro. Theoretical study of xenon adsorption in UO2nanoporous matrices. Journal of Physics: Condensed Matter, IOP Publishing, 2014, 26, 10.1088/0953-8984/26/48/485015. hal-03040139 HAL Id: hal-03040139 https://hal.archives-ouvertes.fr/hal-03040139 Submitted on 4 Dec 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Home Search Collections Journals About Contact us My IOPscience Theoretical study of xenon adsorption in UO2 nanoporous matrices This content has been downloaded from IOPscience. Please scroll down to see the full text. 2014 J. Phys.: Condens. Matter 26 485015 (http://iopscience.iop.org/0953-8984/26/48/485015) View the table of contents for this issue, or go to the journal homepage for more Download details: IP Address: 139.124.20.101 This content was downloaded on 27/11/2014 at 12:59 Please note that terms and conditions apply. Journal of Physics: Condensed Matter
    [Show full text]